Power transmission



y 3 w T. DUNN 2,159,426

POWER TRANSMISSION Filed March 6, 1936 ENTOR WILLIAM DUNN Patented May23, 1939 2,159,426 POWER TRANSMISSION William T. Dunn,

Chrysler Corporation,

Detroit, Micla, or to Highland Park, Mich a corporation of DelawareApplication March is,

9 Claims.

This invention relates to power transmissions especially adapted for usein driving motor vehicles and refers more particularly to improvementsin speed ratio changing mechanisms in motor vehicle drives.

My invention, in its more limited aspects, refers particularly to speedratio changing mechanism more particularly described'in my co-pendingapplication Serial No. 707,048, flied January 18,

In one of its embodiments, my invention provides improvements inautomatic change speed devices and while my improvements are readilyadaptable to a. variety of arrangements of speed ratio gearings and geartrain values, I have preferred to illustrate the principles of myinvention in connection with an automatically operating overdrivingmechanism employing planetary gearing,

$0 One object of my invention is to provide improved safety controllingmeans for a transmission mechanism whereby improper or undesired drivingconditions cannot occur or tend to take place.

A further object of my invention is to provide improved means forcontrolling the operation of the overdrive gearing clutch control, which'is preferably of the automatic centrifugal force operated type, wherebythe driving mechanism cannot be manually or otherwise operated for adirect drive between the driving and driven shafts while the drivebetween said shafts is through the overdrive gearing. Further, myinvention preferably also includes, as a further control and protectionto the transmission mechanism, means for preventing engaging operationof the centrifugal clutch to establish an overdrive, or to tend toestablish such drive, while the driving mechanism is set for a directtwo-way drive between said shaftsj 7 Further objects and advantages ofmy invention will be more apparent hereinafter as the following detaileddescription of one illustrative embodiment of my invention progresses,reference being had to the accompanying drawing in which:

Fig. 1 is a sectional elevational view through my driving mechanismtaken approximately on the line i-i of Fig. 2, and somewhatdiagrammatically illustrating the manually controlled mechanism foreffecting a lock-out of the overrunning and automatic clutches.

Fig. 2 is a sectional elevational view along line 2-2 of Fig. 1,illustrating the automatic clutch It in its disengaged condition.

1936, Serial No. 87,426

is a fragmentary sectional view along the line 3-4 of Fig. 1 showing theoverrunning clutch.

In the drawing, mechanism A interposed bet changing transmission B and Ihave illustrated my driving ween a speed ratio a driven shaft ill,

the latter extending rearwardly to drive the rear wheels (not shown) ofthe motor car or vehicle in the usual well-known manner,

stood that I have elected to it being undershow my invention inassociation with a motor vehicle drive although my invention in itsbroader aspects is not necessarily limited thereto. Furthermore, mydriving mechanism may be used to a dvantage at various other points inthe line of general power transmission between the vehicle engine andthe driven wheels, or between driving or driven means such as shafts ofother types of devices.

The transmission B may be of any suitable type such as the conventionalselector type operated in the selector controls whereby ments may bemade to the tr well-known manner the various adjustthrough usualansmission in order the right as viewed in Fig. 1 for engagement withthe usual reverse idler ii in. order to effect a reverse drive from thenormal direction of drive to the driven shaft Iii. This idler gear 13constantlymeshes with the gear ll.

usual countershaft reverse Thus, by appropriate actuation of the usualtransmission controls, gears ii and I3 may be engaged to reverse stoodthat other manipulatio the drive, it being underns of the transmiss'ionmechanism are adapted to selectively produce other desired speed ratiochanges in the normal direction of rotation for driven shaft Ill.

The power coming from the usual engine or other prime mover (not shown)which may be located forwardly of transmission B, drives thetransmission and the power is taken from this transmission by a powerdriving means or shaft In Fig. l the driving shaft pilots the forwardend" of driven shaft i B. A shiftable clutch i1 is slidably mounted onone of the shafts, such as shaft II, and is continuously with said shaftby splines l8.

drivingly connected This clutch Il has teeth I 9 engageable with teethll of the cylindrical driven member II of the overrunning clutch D, thelatter having cylinders 22 and driving inner cam member 23. In thisinstance this cam member 23 has teeth 24 and is driven from shaft l5 bysplines 25 thereof, teeth 24 being engageable with teeth IQ of shiftableclutch I! when the latter is moved forwardly by arm 25 to lock out theoverrunning clutch.

Cam member 23, for convenience, may be formed with a pawl cage 21carrying one or more pawls 2B of the automatic clutch C.

This automatic clutch may be of the type shown in my aforesaidco-pending application wherein the pawls 28 are yieldingly urgedinwardly to their disengaged or declutched positions by springs 23. At apredetermined desired speed of rotation of the pawls, centrifugal forcewill cause outward movement of the pawls, overcoming the action ofsprings 29, whereby the pawls will be projected for engaged or clutchedpositions. Each pawl 20 may have a yoke portion 30 extending partiallyaround shaft l5 and terminating in a counterbalancing guide end portion3| substantially diametrically opposite the clutching end portion 32 ofeach pawl.

Slots II of shell 34 are driven by the planet carrier 85 having planetgears I6 meshing with a sun gear 31 in this case fixed by brackets 38 tothe casing of transmission 8. Planet gears 35 also mesh with annularinternal gear I! of the cylindrical driving member I].

The planetary gear set is thus adapted at all times to rotate slots IIfrom the driven shaft i ll, through clutch l1 and member ii, at a speedless than that of the pawls 2B which are directly driven from the shaftii. With clutch li positioned as in Fig. l, shaft ll drives shaft Iiithrough the overunning clutch D until, at or above the critical speed,pawls 2B are projected outwardly for engagement with slots 38, and suchengagement will occur when the slots and pawls are substantiallysynchronized. Prior to synchronlzatlon the pawls jump the slots, as moreparticularly described in my aforesaid co-pending application.

Synchronization is provided for by decreasing the speed of the drivingshaft. as by releasing the usual accelerator pedal, and allowing thedriven shaft to overrun the driving shaft by reason of the overunningclutch D.

When clutch C engages for providing a twoway positive drive through theplanetary gear train, the overunning clutch is ineffective and continuesto be so until the pawls are retracted by reason of their rotation belowthe critical speed.

A means for shifting clutch ll forwardly has been provided by shifterarm 28 fixed to horizontal rod iii. A lever II is pivoted at 42, itslower face being in the path of slideabie low and reverse gear and itsupper face being forked for joint connection to horizontal rod 40. Rod40 is slidably mounted in a case ll of the overdrive mechanism and isyieldingly urged rearwardly by spring ll, whenever gear ii is notengaged for reverse drive and whenever a dash control-to be describedlater-is not actuated.

A further means for shifting clutch i I has been incorporated which isindependent of the aforementioned reverse gear control. An arm Iii ismounted and pivoted on case ll, its lower face engaging a sleeve 8 ofrod 40, a suitable remote control-in my drawing a Bowden wire dashcontrol--being attached to arm II and extending to the illustrated dashcontrol. The details of the dash control will be presently set forth.

Lock-out of automatic clutch C is effected by forward movement of pins41 slideable through suitable openings in cam 23 and actuated by theforwardly shifting movement of clutch ll. When these pins are projectedforwardly, they engage the surfaces 48 of the pawl end portions 3|thereby preventing outward movement of the pawls. 28. Springs 49 tend toreturn pins 41 to disengaged position following along with rearwardlyshifting movement of clutch II.

Forwardly shifting of clutch I7 is eflected when gear ii is moved toreverse drive. The lever ll extends into the path of movement of thegear II when the latter is moved rearwardly for engagement with reverseidler l3 as aforesaid. The arrangement is such that when thegear isshifted into engagement with gear I! for establishing the reverse drive,provided that the mechanism is set to properly effect reverse as will bepresently apparent, lever II will be engaged toward the latter part ofthe movement of gear ll so as to move rod Iii forwardly or to the left,thereby shifting clutch il forwardly to engage teeth I! and 24 to lockout or render the automatic clutch C inoperative and the overunningclutch D ineffective and providing a two-way drive between shafts i5 andI0. During the aforesaid movement of rod 40, spring M will be compressedso that on release or forward movement of gear ii, the parts will berestored to positions thereof illustrated provided, however, that othercontrols for the shiftable parts are positionedto accommodate suchreturn movement as will be presently apparent.

In addition to the aforesaid manually operated means for shifting theposition of clutch I! in response to a setting of the reverse gearing oftransmission B, as stated I have also provided a further manuallycontrolled means for shifting the clutch H, at times when permitted bymy improved controlling means, independently of the movement thereofunder the influence of the reverse setting of the transmission. To thisend Bowden wire 50 as diagrammatically illustrated, extends forconvenient manipulation by the vehicle driver, such position beingindicated by the usual dash SI which mounts a handle or knob 52connected to the other end of the Bowden wire Ill. The handle is adaptedfor movementby the hand of the vehicle driver, this handle being guidedfrom its position illustrated to a position in spaced relationship fromdash ii, in which position the guide portion II of the handle registersa notch it thereof with spring pressed ball 55 carried by a guide blockII.

The ball I! and the notches 54 and I1 engageable therewith cooperate toadvise the operator of the proper positioning of handle I! for eflectingthe desired movement of the shifting arm 28 and clutch i'l. In Fig. 1 itwill be noted that the ball 55 is illustrated in engagement with thenotch 51 and in this position spring II is acting to move clutch i1rearwardly or to the position shown. In this position the teeth II arein engagement with the teeth 20 of the cylindrical member II.

It will be noted that when handle I! is pulled outwardly from dash ll,shifter arm II will move against pressure of spring 44 so as to shiftthe clutch l1 and move pins" forwardly, this shifting movement of theclutch I! under actuation of handle 52 being independent of a similarclutch shifting movement under the influence of reverse gear ii. whenthe clutch i1 is shifted forwardly by en agement of notch II with ball55, the clutch device will be maintained in the aforesaid/shiftedposition until the'handle If is 5 restore to the position illustrated,whereuponfirings iii to engage the pawl faces GI and simui-,

taneously prevent the pawls 2! from projecting outwardly, thus renderingthe automatic clutch 15 inoperative When the clutch i1 is shiftedrearwardly by the aforesaid means to the position 11- lustrated, pinsl'l are moved by the pressure of springs 49 tothe position shown.

When clutch 11, pins 41, and the controls are 2 as illustrated, thedriving shaft drives the driven shaft it through the members II and iiof the ,overrunning clutch D, the drive passing from cylindrical member2 M the clutch il, other conditions permitting such action, as will bepres- 25 ently apparent.

with clutch ll in position as shown, the driving and driven shafts itand i0 respectively will be connected for a forward direct drive throughcam 23, rollers 22,- cyllndrlcal member Ii, and so clutch i'i when theautomatic clutch is disengaged. However, when the automatic clutch isengaged the drive between driving shaft ii and driven shaft ill will beaccomplished with an overdrive action or increase in speed of the drivena5 shaft over the driving shaft through cam 28, au-

, tomatic clutch C. planet gears 36, cylindrical member 2i, and ,clutchl1.

when the automatic clutch is engaged for the overdrive, it is impossibleto shift clutch II for- 40 wardly or to the left of the position shownto at tempt lock-out of the ovemmning and automatic clutches for adirect drive, as pins 41 will strike side faces of clutch pawls 2i. r

what I claim is: 45 1. In a power transmission mechanism. a drive shaft,a driven shaft, means including-a shiftahle clutch device driven by oneof said shafts and adapted to provide a direct drive between saidshafts, means including a gearj'train for drivin 50 said driven sha tfrom said drive shim. at a speed ratio different from said directdrivmsaid speed ratio driving means including driving'and driven membersrespectively adapted for driving connect on with said' shafts, saidspeed ratio driving 58 means further including relatively movableclutching structures adapted when engaged to provide a drive throughsaid gear train, manually operable means for shifting said clutch devicei'nto a position providing said direct drive, 60 and a controlpinoperably disposed between said clutch device and one of saidclutching structune for r'eleasablylocking said manually operable meansagainst operation to shift said clutch device into position tending toestablish said di- 65 met drive when said clutching structuresareengaged.

2. In a power transmission mechanism, a drive shaft, a driven shaft,means including a shiftable clutch device driven by one, of said shaftsand 70 adapted to provide a direct drive between said shafts, meansincluding a gear train for drivin said driven shaft from said driveshaft at a speed ratio different from said direct drive, said speedratio driving including driving and driven is mes for -driving nectionwith said shafts, said speed ratio drivin means further includingrelatively movable clutchingstructures adapted when engaged to provide adrive through said gear train, manually operable means for shifting saidclutch de- 5 vice into a position providing said direct drive. and acontrol pin operably disposed between said clutch device and one of saidclutching structures for releasably locking said clutching structuresagainst relative clutching movement while said clutch device is in saidposition for'providlng 1 said direct drive.

3. In a power transmission mechanism, a drive shaft, a driven shaft,means including a shiftable clutch device driven by one of said shaftsand adapted to provide a direct drive between said shafts, meansincluding a gear train for driving said driven shaft from said driveshaft at a speed ratio different from said direct drive, said speedratio driving means including driving and driven members respectivelyadapted for driving connection with said shafts, said speed ratiodriving means further including relatively movable clutching structuresadapted when engaged to provide a drive through said gear train,manually operable means for shifting said clutch device into a positionproviding said direct drive, manually controlled operating means forreversing the normal direction of drive of said drive shaft, and acontrol pin disposed between said clutch device and one of saidclutching strllctures and adapted for operation in response to selectiveoperation'of said manually operable means and said manually controlledreversing means for rendering said clutching structures inoperative forsaid relative movement.

4. In a drive for a' motor vehicle havinga power driving shaft and ashaft driven therefrom and adapted to drive the vehicle, said drivingand driven shafts being in axial alignment, overrun- 40 ning clutchmeans lntermed'ate said shafts for transmitting a releasable one-waydirect drive therebetween, rotatable clutching structures one having aclutching element adapted to clutch with the other in response tosubstantially synchronized rotation of said clutching structures at orabove a pre-determined speed to provide a releasable positive drivingconnection therebetween, means for driving one of said structures fromsaid driving shaft, means for driving the 5 other of said structuresfrom said driven shaft. at least one of said driving-means including agear train adaptedto drive itsassociated clutching structure at a speeddiflerent from that imparted to the other of said structures when saiddriving shaft drives said driven. shaft through said over-runningclutch, said overrunning clutch being rendered inoperative in responseto clutching of said structures, manually controlled clutch meansshiftable relative to-each of said clutching on structures for lookingout said overrunning clutch to provide a direct two-way drive betweensaid driving and driven shafts, and acontrol pin operably disposedbetween said shiftable clutch means and said clutching element forlocking said man- 05 ually controlled clutch means said-shiftmovement. I

In a power transmission mechanism, a drive shaft, a driven shaft, clutchmeans drivingly connected to said shafts for transmitting a dimet drivetherebetwe'en, means including a gear train for driving said drivenshaft from said drive shaft at a-speed ra diflerent-from said drive,said speed ratio ving means including driving and drivenmembersrespectively adapted fl for driving connection with said shafts,said speed ratio driving means further including relatively movableclutching structures adapted when engaged to provide a drive throughsaid gear train, one of said clutching structures being sotuated inresponse to centrifugalforce actins thereon into clutching engagementwith the other of said clutching structures in response to substantiallysynchronized rotation of said clutching structures at or above apredetermined speed, a reciprocatory control pin disposed longitudinallyadjacent one of said shafts between said direct drive clutch means andsaid centrifugal force actuated clutching structure to control theoperation of the last said clutching structure relative to the operationof said direct driven clutch means, and a spring yieldingly urging saidcontrol pin in one direction of reciprocatory movement thereof.

6. In a power transmission mechanism, a drive shaft, a driven shaft,clutch means drivingly connected to said shafts for transmitting adirect drive therebetween, means including a gear train for driving saiddriven shaft from said drive shaft at a speed ratio diflerent from saiddirect drive, said speed ratio driving means including driving anddriven members respectively adapted for driving connection with saidshafts, said speed ratio driving means further including relativelymovable clutching structures adapted when engaged to provide a drivethrough said gear train, one of said clutching structures being actuatedin response to centrifugal force acting thereon into clutchingengagement with the other of said clutching structures in response tosubstantially synchronized rotation of said clutching structures at orabove a predetermined speed, said clutch means being adapted to releasesaid direct drive to facilitate synchronization of said clutchingstructures, and a control pin mounted for reciprocation in a directionparallel to the axis of one of said shafts and being disposed betweensaid centrifugal force actuated clutching structure and a part of saiddirect drive clutch means to control the operation of the last saidclutching structure relative to the operation of said clutch means.

7. In a motor vehicle drive, a driving shaft, a driven shaft alignedtherewith, releasable direct drive means betweenthe driving and drivenshafts, said releasable direct drive means being so constructed andarranged as to permit relative movement between said shafts in responseto a reduction in the speed of one of said shafts relative to the speedof the other of said shafts, supplemental driving means for driving thedriven shaft from the driving shaft at a speed ratio different than saiddirect drive, said supplemental driving means including clutching meansfor controlling the drive therethrough, said clutching means includingclutching members one of which is adapted for centrifugal force movementinto engagement with the other, and means including an element movablerelatively with respect to said shafts and clutching members intoengagement with one of said clutching members for controlling theoperation of said clutching means to prevent centrifugal force movementof said movable ciutching member toward the other of said clutchingmembers.

8. In a motor vehicle drive, an axially stationary driving shaft, anaxially stationary driven shaft aligned therewith, overrunning-clutchdirect-driving means between the driving and driven shafts, means fordirectly drivingly connecting said shafts independently of saidoverrunning clutch, supplemental driving means for driving the drivenshaft from the driving shaft at a speed ratio different than said directdrive, said supplemental driving means including clutching means forcontrolling the drive therethrough, and latching means operablyassociated with said clutching means for preventing operation thereof inresponse to operation of said direct drive connecting means.

9. In a motor vehicle, a driving shaft aligned therewith, releasabledirect drive means between the driving and driven shafts foraccommodating relative movement therebetween. supplemental driving meansfor driving the driven shaft from the driving shaft at a speed ratiodifferent than said direct drive, said supplemental driving meansincluding clutching means operable in response to a predetermined speedof rotation of at least one of said shafts to automatically establishsaid speed ratio drive when said relative movement takes place betweensaid shafts. said clutching means including relatively rotatableclutching members one of which is adapted for centrifugal force movementfor engagement with the other when the speeds thereof are substantiallysynchronized, and means movable relative to said shafts and clutchingmembers into a position of engagement with said centrifugal forceclutching member for preventing movement thereof.

WILLIAM T. DUNN.

CERTIFICATE OF CORRECTION.

Patent No. 2,159,1r26.

WILLIAM I.

DUNN.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page ifirst column, line 16, claim 5, for the word "driven" read drive; andthat the said Letters Patent should beread with this correction thereinthat the same may conform to the record of the case in the PatentOffice.

Signed and sealed this 25th day of July, A. D. 1939.

(Seal) Henry Van Arsdale, Acting Commissioner of Patents.

for driving connection with said shafts, said speed ratio driving meansfurther including relatively movable clutching structures adapted whenengaged to provide a drive through said gear train, one of saidclutching structures being sotuated in response to centrifugalforceactins thereon into clutching engagement with the other of saidclutching structures in response to substantially synchronized rotationof said clutching structures at or above a predetermined speed, areciprocatory control pin disposed longitudinally adjacent one of saidshafts between said direct drive clutch means and said centrifugal forceactuated clutching structure to control the operation of the last saidclutching structure relative to the operation of said direct drivenclutch means, and a spring yieldingly urging said control pin in onedirection of reciprocatory movement thereof.

6. In a power transmission mechanism, a drive shaft, a driven shaft,clutch means drivingly connected to said shafts for transmitting adirect drive therebetween, means including a gear train for driving saiddriven shaft from said drive shaft at a speed ratio diflerent from saiddirect drive, said speed ratio driving means including driving anddriven members respectively adapted for driving connection with saidshafts, said speed ratio driving means further including relativelymovable clutching structures adapted when engaged to provide a drivethrough said gear train, one of said clutching structures being actuatedin response to centrifugal force acting thereon into clutchingengagement with the other of said clutching structures in response tosubstantially synchronized rotation of said clutching structures at orabove a predetermined speed, said clutch means being adapted to releasesaid direct drive to facilitate synchronization of said clutchingstructures, and a control pin mounted for reciprocation in a directionparallel to the axis of one of said shafts and being disposed betweensaid centrifugal force actuated clutching structure and a part of saiddirect drive clutch means to control the operation of the last saidclutching structure relative to the operation of said clutch means.

7. In a motor vehicle drive, a driving shaft, a driven shaft alignedtherewith, releasable direct drive means betweenthe driving and drivenshafts, said releasable direct drive means being so constructed andarranged as to permit relative movement between said shafts in responseto a reduction in the speed of one of said shafts relative to the speedof the other of said shafts, supplemental driving means for driving thedriven shaft from the driving shaft at a speed ratio different than saiddirect drive, said supplemental driving means including clutching meansfor controlling the drive therethrough, said clutching means includingclutching members one of which is adapted for centrifugal force movementinto engagement with the other, and means including an element movablerelatively with respect to said shafts and clutching members intoengagement with one of said clutching members for controlling theoperation of said clutching means to prevent centrifugal force movementof said movable ciutching member toward the other of said clutchingmembers.

8. In a motor vehicle drive, an axially stationary driving shaft, anaxially stationary driven shaft aligned therewith, overrunning-clutchdirect-driving means between the driving and driven shafts, means fordirectly drivingly connecting said shafts independently of saidoverrunning clutch, supplemental driving means for driving the drivenshaft from the driving shaft at a speed ratio different than said directdrive, said supplemental driving means including clutching means forcontrolling the drive therethrough, and latching means operablyassociated with said clutching means for preventing operation thereof inresponse to operation of said direct drive connecting means.

9. In a motor vehicle, a driving shaft aligned therewith, releasabledirect drive means between the driving and driven shafts foraccommodating relative movement therebetween. supplemental driving meansfor driving the driven shaft from the driving shaft at a speed ratiodifferent than said direct drive, said supplemental driving meansincluding clutching means operable in response to a predetermined speedof rotation of at least one of said shafts to automatically establishsaid speed ratio drive when said relative movement takes place betweensaid shafts. said clutching means including relatively rotatableclutching members one of which is adapted for centrifugal force movementfor engagement with the other when the speeds thereof are substantiallysynchronized, and means movable relative to said shafts and clutchingmembers into a position of engagement with said centrifugal forceclutching member for preventing movement thereof.

WILLIAM T. DUNN.

CERTIFICATE OF CORRECTION.

Patent No. 2,159,1r26.

WILLIAM I.

DUNN.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page ifirst column, line 16, claim 5, for the word "driven" read drive; andthat the said Letters Patent should beread with this correction thereinthat the same may conform to the record of the case in the PatentOffice.

Signed and sealed this 25th day of July, A. D. 1939.

(Seal) Henry Van Arsdale, Acting Commissioner of Patents.

